Endless flexible drive belt and pulley arrangements are commonly used in motor vehicles as well as in other types of machinery. There have been many different types of flexible drive belts used on motor vehicles over time but the most common for current model vehicles is a multi-rib belt commonly referred to as a ‘serpentine belt’. This type of belt is typically applied to drive pulleys of the engine and then a tensioning device is applied to maintain the correct tension to prevent belt slippage. It is recommended that the drive belts be replaced in accordance with the manufacturer's service recommendations. To carry out this service operation the tensioner device is relaxed, the old belt is removed and replaced by a new belt, and the tensioner is then reapplied. There are no special tools required to carry out this service task.
Of more recent times vehicle manufacturers have moved to a new ‘stretch fit’ multi-rib drive belt technology, as produced by The Gates Corporation (Denver, USA). This has removed the need for expensive tensioning devices but it has created a disadvantage when it comes time to carrying out maintenance of these belts. They are fitted at the factory using specialised installation equipment and when replacement is required in the field, the recommended service procedure is to cut the old belt from the pulleys. Then using model specific tools the new belt is wound back onto the pulleys. This creates a situation whereby a service agent must have available multiple installation tools such as part numbers SFT001, SFT002 A+B and SFT003 (to name a few) as manufactured by The Gates Corporation. These installation tools are both expensive and difficult to use as there are multiple components that require assembly and adjustment to operate.
Another disadvantage of the ‘stretch fit’ flexible belt is that there is no current method to allow removal and reuse of the belt. If a stretch belt has recently been replaced and then an accessory of the engine (ie. alternator, power steering pump, water pump or air conditioning compressor) fails a short time later, the newly replaced drive belt must be cut and another new belt fitted. This adds additional service cost for the customer.
Although tools have been developed for stretch ‘serpentine’ belt installation, they generally have a number of disadvantages. U.S. patent application Ser. No. 12/596,041 and U.S. Pat. No. 6,402,649, for example, each describe a tool for installing a flexible drive belt. A disadvantage of each of these tools, however, is that each tool must first be mounted to a shaft of the pulley by way of a positioning and retaining bolt.